1. Field of the Invention
The present invention relates to a self-testing method, and more particularly to a self-testing method of electrostatic dissipation abilities for an ion generating device.
2. Description of the Related Art
The demand for semiconductor products steadily increases, and consumers turn to look for lighter, thinner, shorter and smaller electronic products. Therefore, manufacturers continually seek to minimize the feature size of electronic parts to comply with the demands of the electronic products markets. In addition, manufacturers have to improve their semiconductor manufacturing processes to obtain breakthrough technologies.
The manufacturing costs and added value of semiconductor products are high, and the yield rate of products is a crucial factor in determining the costs of semiconductor chips and other electronic products. Therefore, each phase of the manufacturing process, as well as the semiconductor manufacturing equipment, goes through numerous tests to guarantee the yield rate of finished electronic products.
As the semiconductor manufacturing process reaches the 22 nm or even 20 nm node, the semiconductor products are easily damaged by electrostatic charge. Static electricity arises from ion movements due to contact between objects, which imparts positive or negative charge to an object. Because of electrostatic discharge, small semiconductor products are easily pierced, burned or damaged. Therefore, how to prevent static electricity is an important issue for semiconductor manufacturers to address.
With reference to FIG. 1, illustrating an aspect of Taiwan Invention No. I359235, “Detecting device of an ionic fan for mechanical equipment”, mechanical equipment has a central processing unit 23 to control each device, and inside a cover there is at least an ionic fan 24 to dissipate static electricity. The ionic fan 24 is connected to a detecting device 25, and inside the detecting device 25 there is a microprocessor unit 254 and a plurality of detecting units 251. The plural detecting units 251 are connected to the ionic fan 24 by a circuit that can transmit detecting signals from the ionic fan to the microprocessor unit 254. After performing a comparison, the microprocessor unit 254 transmits a detecting result, through the central processing unit 23 to a display unit 231 to display the detecting result.
The prior art detecting device for an ionic fan is convenient for workers to immediately acknowledge and fix malfunctions of the ionic fan external to the mechanical equipment. However, it cannot actively control the number of positive and negative ions output by the ionic fan 24, so the semiconductor manufacturing process is forced to stop and the manufacturing time is impacted.
Because static electricity will not disappear voluntarily, as long as static electricity exists, it can cause damage which can lead to a loss of millions or even ten millions of dollars. To improve the reliability of products and to prevent damage from static electricity, active electrostatic dissipation devices need to be improved.
Therefore, on Jun. 10, 2013, the applicant of this application filed Taiwanese patent, application no. 102120596, entitled “An active sensing feedback ion generating device”. The above invention can adjust voltage in accordance with the sensed ion numbers, and respond by adjusting the ion generating device; the device should correspond to the positive and negative ion output numbers to achieve the goal of active sensing and response. However, if the positive and negative ion output function of the ion generating device can not comply with the output requirements (such as due to a contaminated ion discharge needle), although the device will continuously respond with a balanced voltage of ions, it cannot neutralize the electrostatic charge and so the tested semiconductor will still be damaged by static electricity.
To solve this problem, the electrostatic dissipation capability of the ion generating device needs to be examined. However, during examination the semiconductor manufacturing line needs to be stopped, and has to empty out semiconductor products, so the examination will consume much more labor and time. Therefore, it is desirable to provide a detecting method for the electrostatic dissipation capability for an ion generating device without impacting a manufacturing line.